Unable to retrieve all attachments from forwarded Outlook emails using Graph API

We have integrated Outlook with our system using Microsoft Graph API and subscribed to message events. Whenever we receive an event, we process the email message at our end.

Currently, we are facing an issue related to attachments in forwarded email conversations.

Scenario

1. An email conversation contains multiple replies.
2. Some of these replies contain attachments.
3. When a user forwards the entire email thread, Outlook generates a forwarded email that includes the conversation history in the email body.

Problem

When we receive the forwarded email event and fetch the message details using the Microsoft Graph API, we observe the following:

• The forwarded email only contains the latest reply's attachment.
• Attachments from earlier replies in the thread are not included in the forwarded message attachments.
• In some cases:
  • The first reply contains an attachment.
  • Subsequent replies do not contain attachments.
  • When the user forwards the email, the forwarded message JSON shows: hasAttachments: false

But, the forwarded email body still contains the previous conversation that had attachments.

Our Questions

Is there a way to retrieve all attachments from the entire email thread when a conversation is forwarded?

Can we retrieve these attachments using the current user's access token via Microsoft Graph API?

1. If there is a way, please also let us know how we can identify forwarded emails using the Microsoft Graph API, so that we can apply this solution only for forwarded emails.

Our Requirement

We need a reliable solution that works in production to ensure that all attachments from the email conversation are retrieved, even when the email thread is forwarded.

This issue is currently impacting our production system, so we would greatly appreciate any guidance on the correct approach.

Thank you in advance for your support.